For those of you with 02-04 rockford fosgate systems that are looking for a true AUX in, I successfully modded my 6disc fosgate in my 2003 se xterra for an aux input!! All you have to do is soldered 2 wires and attach the ground to HU(head unit)case and it works, simplest mod ever. When you plug your mp3 in, it just cuts out the cd players music and plays the aux music! Couldn't be more happy with this mod as it doesn't sacrifice anything and everything still works.

What you need for this project:
-one male-male auxiliary cable $5-15
-soldering iron
-solder
-philips screwdriver, mid-sized
-hot glue gun w/ a refill
-x-acto knife, or w.e to cut the one end off the aux cable and to strip wires!

1. Cut one end off aux cable, there will be 3 wires, mine had red(was right ch), white(was left ch), and black(ground)yours might be different if it is check out the schematic for a aux plug, and tear apart the end you just cut off to see what attaches where!

2.Take out stereo, if you are not sure how to get to it here you go:
1.Pull up on central part by shifter (marked with ovals) it should just pop up with a little bit of force
2.Once that is up it should reveal 2 screws that were hiding behind it, and the other 2 are where showed in this picture[img][img]http://www.freeimagehosting.net/uploads/66a2e5f087.jpg[/img][/img]
3.once all the screws are off the dash panel will come off, disconnect the hazard, and cig lighter.
4.now you can see the stereo, unscrew 4 screws, and take off connecting wires, it should be free now.

3.Take off front face plate with small screw driver and just lift the tabs on top and sides should come off then
[img][img]http://www.freeimagehosting.net/uploads/2377cd538f.jpg[/img][/img]
4.unscrew these then bottom plate should come off:
[img][img]http://www.freeimagehosting.net/uploads/ab20688841.jpg[/img][/img]

5.find this on the circuit board this is your diagram of what goes where, it corresponds to the "legs" sticking out over there. Note you will have to add some solder to the "legs" in order to attach the wires... or at least it will make it easier. [img][img]http://www.freeimagehosting.net/uploads/d1883787ab.jpg[/img][/img]
this is my real aux cable i used first picture was a test one:[img][img]http://www.freeimagehosting.net/uploads/th.a628193ab3.jpg[/img][/img]

6.Figure out were you want to lead the aux cable in and then solder it. Once you have finished soldering the right wire and left wire take the remaining ground wire and stick it up to go through the bottom of the HU case. Check to see if it will fit through one of the HU case holes(you may also have to add wire to lengthen it so you can wrap it around and solder it for a good ground. This was my test idea just to wrap and tape it to the case to check the ground and it all[img][img]http://www.freeimagehosting.net/uploads/ade958426e.jpg[/img][/img]
If your not sure about the connections, go hook it back up to the car and test it to see if everything works. When everything works take off bottom HU case again and now make sure everything is secure.... hot glue it! I also took the soldering iron and melted the aux cable a bit to form a bulge where it fed through so it wouldn't get yanked out.

7. Should be done now, put it all back together!

8.Have fun listening to your mp3, ipod, zune, w.e!!!

Any luck people? Have you got it working? Has any one tried it?

Thanks for the very helpful procedures on adding an AUX in / mp3 jack to the Xterra stock radio. I decided that I liked the idea, but was not skilled enough to solder to the points that you chose. I asked a friend for help and found alternative soldering points that are much easier to solder to and it worked! The sound is awesome. There is no quiet sound problem like I've read mentioned in other posts/forums. I can crank it way up. Louder than I need. It's a 2004 Xterra. Here are some photos of what I did.

This one shows the general location of where I soldered to. This is the CD changer board. Sorry that I don't have pictures on how I disassembled it to this point, but others have posted detailed disassembly photos.

This one is zoomed in and shows the details of the soldering points:


Here's another zoomed out general location:

Here is one showing things more assembled back together and the wires hanging out the back:

Here are the wires hanging out the front:

Here is after soldering the wires to the aux in / mp3 jack:

Here is where I installed the aux in / mp3 jack on the console. It doesn't show it, but I added a bunch of hot glue gun glue to the back of the console that is shown in this picture. This made the jack feel much more solid and I highly recommend:


So with this post I hope I'm helping someone else out as much as you helped me out. Long live the internet and the free sharing of ideas!

Interesting. The points are clearly marked Left Channel, Right Channel and Aux Ground (which would be the common between left and right).

Question though, how does the input work in practice? How does the H/U know to use the signals you are inputting via the 3.5mm plug, versus some other function (FM/AM, CD), etc? What do you have to do to the H/U to get it to accept this input? I ask because the points you used are clearly for an Aux. In, yet others have reported needing to use a blank CD and this new signal rides on top of the blank CD (i.e., the H/U thinks it's playing a CD). But it this IS a true Aux. In, how does the H/U recognize it? (BTW - I have the same H/U in my '03, which is why I'm asking!)

Thanks,
-G

Hey, 686, I tried your method of doing it and was curious, is it just as loud as the CD's or is the sound diminished. This was the first thing I've ever soldered, and just curious if it was a rookie mistake or not. Also, when I use my iPod, I get engine interference(a sort of "whirring" that increases with rpms) but with my Droid it doesn't occur... Is that odd? Well hopefully you'll poke your head in on this thread, although your last post on it was a few months ago.

WAHOO some hits! Thought this wasn't even getting use! but i guess no reply are better than a ton saying its not working!

@kowpeki nice job! stoked you could make it work and that my ideas possibly helped yours!

@ Gonzo-2: I think it might just be "au. grd" for audio ground? but that is just a guess. How I have it set up it will just cut out the cd audio and play, not over it as you can't hear the cd audio if you turn it way up (I use any cd(all with music on them also)), I have no clue how it works... but it seems to haha when it does change cds all audio stops, as a cd does have to be spinning for it to work
I guess it isn't a true aux in, but best i have found!

@djsfrigidX: I would say it's a little quieter than cds, but it also really depends on the type of MP3 player you have, I was rocking a sansa clip+, which I found to be a lot louder(at par with cds) than my recent sony E series, Sounds quality is great in my opinion. I haven't noticed any noises or whining with increase of rpm's with my mp3 players, but Ipods are strange, as i think i have experienced the same results as you are describing. So maybe it is just ipods that dont work that well? OR maybe check your solder points, and especially the ground! I didnt have pictures of how i hot glued around the solder points, but this could also be helping in isolating and grounding everything? yes i pop in quite often usually to see no posts!

http://www.xterraownersclub.com/forums/ubbthreads.php?ubb=showflat&Number=289045&page=3 scroll down 1/3rd page This post of mine has the pictures all already on there.... shit the bed on posting them on this one :P

I also upgraded the aux cable, one shown was head phone wire for testing purposes, pic with red, white, and a thick black cable is of the new one (all melted to the shit though haha)

Yeah, kinda sorry about posting before I really had a field test... As far as the RPM "whirring" noise goes, it would seem to happen only when I am charging my iPod from DC... Otherwise it is gracious sound quality. Glad to see this thread still piques your interest.

~drunk Dalton

Sorry for taking so long to respond. I don't monitor this forum very often. Yes, the Aux Ground is goes straight to the aux jack ground, common for both left and right. In practice, yes, I have to put a CD in the head unit and play it. Just like 686cody686, I do not know how it works, but none of the "playing" CD bleeds through the system. There is not additional noise either, no engine whine. It is a clean sound. There is no inability to make it loud as I want. Note though, I have only tested with an iPOD.

Many thanks to kowpeki for the instructions. Just wanted to chime in and confirm great results with the method he posted. Took a bit of patience with the soldering, but well worth the effort!

Now my 04 SE can play audio from my iPhone--a CD has to be playing, but it cuts over automatically. No switch to mess with, no noise, no hum, great sound!